libstdc++
stl_map.h
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00001 // Map implementation -*- C++ -*-
00002 
00003 // Copyright (C) 2001-2017 Free Software Foundation, Inc.
00004 //
00005 // This file is part of the GNU ISO C++ Library.  This library is free
00006 // software; you can redistribute it and/or modify it under the
00007 // terms of the GNU General Public License as published by the
00008 // Free Software Foundation; either version 3, or (at your option)
00009 // any later version.
00010 
00011 // This library is distributed in the hope that it will be useful,
00012 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00013 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014 // GNU General Public License for more details.
00015 
00016 // Under Section 7 of GPL version 3, you are granted additional
00017 // permissions described in the GCC Runtime Library Exception, version
00018 // 3.1, as published by the Free Software Foundation.
00019 
00020 // You should have received a copy of the GNU General Public License and
00021 // a copy of the GCC Runtime Library Exception along with this program;
00022 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00023 // <http://www.gnu.org/licenses/>.
00024 
00025 /*
00026  *
00027  * Copyright (c) 1994
00028  * Hewlett-Packard Company
00029  *
00030  * Permission to use, copy, modify, distribute and sell this software
00031  * and its documentation for any purpose is hereby granted without fee,
00032  * provided that the above copyright notice appear in all copies and
00033  * that both that copyright notice and this permission notice appear
00034  * in supporting documentation.  Hewlett-Packard Company makes no
00035  * representations about the suitability of this software for any
00036  * purpose.  It is provided "as is" without express or implied warranty.
00037  *
00038  *
00039  * Copyright (c) 1996,1997
00040  * Silicon Graphics Computer Systems, Inc.
00041  *
00042  * Permission to use, copy, modify, distribute and sell this software
00043  * and its documentation for any purpose is hereby granted without fee,
00044  * provided that the above copyright notice appear in all copies and
00045  * that both that copyright notice and this permission notice appear
00046  * in supporting documentation.  Silicon Graphics makes no
00047  * representations about the suitability of this software for any
00048  * purpose.  It is provided "as is" without express or implied warranty.
00049  */
00050 
00051 /** @file bits/stl_map.h
00052  *  This is an internal header file, included by other library headers.
00053  *  Do not attempt to use it directly. @headername{map}
00054  */
00055 
00056 #ifndef _STL_MAP_H
00057 #define _STL_MAP_H 1
00058 
00059 #include <bits/functexcept.h>
00060 #include <bits/concept_check.h>
00061 #if __cplusplus >= 201103L
00062 #include <initializer_list>
00063 #include <tuple>
00064 #endif
00065 
00066 namespace std _GLIBCXX_VISIBILITY(default)
00067 {
00068 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
00069 
00070   template <typename _Key, typename _Tp, typename _Compare, typename _Alloc>
00071     class multimap;
00072 
00073   /**
00074    *  @brief A standard container made up of (key,value) pairs, which can be
00075    *  retrieved based on a key, in logarithmic time.
00076    *
00077    *  @ingroup associative_containers
00078    *
00079    *  @tparam _Key  Type of key objects.
00080    *  @tparam  _Tp  Type of mapped objects.
00081    *  @tparam _Compare  Comparison function object type, defaults to less<_Key>.
00082    *  @tparam _Alloc  Allocator type, defaults to
00083    *                  allocator<pair<const _Key, _Tp>.
00084    *
00085    *  Meets the requirements of a <a href="tables.html#65">container</a>, a
00086    *  <a href="tables.html#66">reversible container</a>, and an
00087    *  <a href="tables.html#69">associative container</a> (using unique keys).
00088    *  For a @c map<Key,T> the key_type is Key, the mapped_type is T, and the
00089    *  value_type is std::pair<const Key,T>.
00090    *
00091    *  Maps support bidirectional iterators.
00092    *
00093    *  The private tree data is declared exactly the same way for map and
00094    *  multimap; the distinction is made entirely in how the tree functions are
00095    *  called (*_unique versus *_equal, same as the standard).
00096   */
00097   template <typename _Key, typename _Tp, typename _Compare = std::less<_Key>,
00098             typename _Alloc = std::allocator<std::pair<const _Key, _Tp> > >
00099     class map
00100     {
00101     public:
00102       typedef _Key                                      key_type;
00103       typedef _Tp                                       mapped_type;
00104       typedef std::pair<const _Key, _Tp>                value_type;
00105       typedef _Compare                                  key_compare;
00106       typedef _Alloc                                    allocator_type;
00107 
00108     private:
00109 #ifdef _GLIBCXX_CONCEPT_CHECKS
00110       // concept requirements
00111       typedef typename _Alloc::value_type               _Alloc_value_type;
00112 # if __cplusplus < 201103L
00113       __glibcxx_class_requires(_Tp, _SGIAssignableConcept)
00114 # endif
00115       __glibcxx_class_requires4(_Compare, bool, _Key, _Key,
00116                                 _BinaryFunctionConcept)
00117       __glibcxx_class_requires2(value_type, _Alloc_value_type, _SameTypeConcept)
00118 #endif
00119 
00120     public:
00121       class value_compare
00122       : public std::binary_function<value_type, value_type, bool>
00123       {
00124         friend class map<_Key, _Tp, _Compare, _Alloc>;
00125       protected:
00126         _Compare comp;
00127 
00128         value_compare(_Compare __c)
00129         : comp(__c) { }
00130 
00131       public:
00132         bool operator()(const value_type& __x, const value_type& __y) const
00133         { return comp(__x.first, __y.first); }
00134       };
00135 
00136     private:
00137       /// This turns a red-black tree into a [multi]map.
00138       typedef typename __gnu_cxx::__alloc_traits<_Alloc>::template
00139         rebind<value_type>::other _Pair_alloc_type;
00140 
00141       typedef _Rb_tree<key_type, value_type, _Select1st<value_type>,
00142                        key_compare, _Pair_alloc_type> _Rep_type;
00143 
00144       /// The actual tree structure.
00145       _Rep_type _M_t;
00146 
00147       typedef __gnu_cxx::__alloc_traits<_Pair_alloc_type> _Alloc_traits;
00148 
00149     public:
00150       // many of these are specified differently in ISO, but the following are
00151       // "functionally equivalent"
00152       typedef typename _Alloc_traits::pointer            pointer;
00153       typedef typename _Alloc_traits::const_pointer      const_pointer;
00154       typedef typename _Alloc_traits::reference          reference;
00155       typedef typename _Alloc_traits::const_reference    const_reference;
00156       typedef typename _Rep_type::iterator               iterator;
00157       typedef typename _Rep_type::const_iterator         const_iterator;
00158       typedef typename _Rep_type::size_type              size_type;
00159       typedef typename _Rep_type::difference_type        difference_type;
00160       typedef typename _Rep_type::reverse_iterator       reverse_iterator;
00161       typedef typename _Rep_type::const_reverse_iterator const_reverse_iterator;
00162 
00163 #if __cplusplus > 201402L
00164       using node_type = typename _Rep_type::node_type;
00165       using insert_return_type = typename _Rep_type::insert_return_type;
00166 #endif
00167 
00168       // [23.3.1.1] construct/copy/destroy
00169       // (get_allocator() is also listed in this section)
00170 
00171       /**
00172        *  @brief  Default constructor creates no elements.
00173        */
00174 #if __cplusplus < 201103L
00175       map() : _M_t() { }
00176 #else
00177       map() = default;
00178 #endif
00179 
00180       /**
00181        *  @brief  Creates a %map with no elements.
00182        *  @param  __comp  A comparison object.
00183        *  @param  __a  An allocator object.
00184        */
00185       explicit
00186       map(const _Compare& __comp,
00187           const allocator_type& __a = allocator_type())
00188       : _M_t(__comp, _Pair_alloc_type(__a)) { }
00189 
00190       /**
00191        *  @brief  %Map copy constructor.
00192        *
00193        *  Whether the allocator is copied depends on the allocator traits.
00194        */
00195 #if __cplusplus < 201103L
00196       map(const map& __x)
00197       : _M_t(__x._M_t) { }
00198 #else
00199       map(const map&) = default;
00200 
00201       /**
00202        *  @brief  %Map move constructor.
00203        *
00204        *  The newly-created %map contains the exact contents of the moved
00205        *  instance. The moved instance is a valid, but unspecified, %map.
00206        */
00207       map(map&&) = default;
00208 
00209       /**
00210        *  @brief  Builds a %map from an initializer_list.
00211        *  @param  __l  An initializer_list.
00212        *  @param  __comp  A comparison object.
00213        *  @param  __a  An allocator object.
00214        *
00215        *  Create a %map consisting of copies of the elements in the
00216        *  initializer_list @a __l.
00217        *  This is linear in N if the range is already sorted, and NlogN
00218        *  otherwise (where N is @a __l.size()).
00219        */
00220       map(initializer_list<value_type> __l,
00221           const _Compare& __comp = _Compare(),
00222           const allocator_type& __a = allocator_type())
00223       : _M_t(__comp, _Pair_alloc_type(__a))
00224       { _M_t._M_insert_unique(__l.begin(), __l.end()); }
00225 
00226       /// Allocator-extended default constructor.
00227       explicit
00228       map(const allocator_type& __a)
00229       : _M_t(_Compare(), _Pair_alloc_type(__a)) { }
00230 
00231       /// Allocator-extended copy constructor.
00232       map(const map& __m, const allocator_type& __a)
00233       : _M_t(__m._M_t, _Pair_alloc_type(__a)) { }
00234 
00235       /// Allocator-extended move constructor.
00236       map(map&& __m, const allocator_type& __a)
00237       noexcept(is_nothrow_copy_constructible<_Compare>::value
00238                && _Alloc_traits::_S_always_equal())
00239       : _M_t(std::move(__m._M_t), _Pair_alloc_type(__a)) { }
00240 
00241       /// Allocator-extended initialier-list constructor.
00242       map(initializer_list<value_type> __l, const allocator_type& __a)
00243       : _M_t(_Compare(), _Pair_alloc_type(__a))
00244       { _M_t._M_insert_unique(__l.begin(), __l.end()); }
00245 
00246       /// Allocator-extended range constructor.
00247       template<typename _InputIterator>
00248         map(_InputIterator __first, _InputIterator __last,
00249             const allocator_type& __a)
00250         : _M_t(_Compare(), _Pair_alloc_type(__a))
00251         { _M_t._M_insert_unique(__first, __last); }
00252 #endif
00253 
00254       /**
00255        *  @brief  Builds a %map from a range.
00256        *  @param  __first  An input iterator.
00257        *  @param  __last  An input iterator.
00258        *
00259        *  Create a %map consisting of copies of the elements from
00260        *  [__first,__last).  This is linear in N if the range is
00261        *  already sorted, and NlogN otherwise (where N is
00262        *  distance(__first,__last)).
00263        */
00264       template<typename _InputIterator>
00265         map(_InputIterator __first, _InputIterator __last)
00266         : _M_t()
00267         { _M_t._M_insert_unique(__first, __last); }
00268 
00269       /**
00270        *  @brief  Builds a %map from a range.
00271        *  @param  __first  An input iterator.
00272        *  @param  __last  An input iterator.
00273        *  @param  __comp  A comparison functor.
00274        *  @param  __a  An allocator object.
00275        *
00276        *  Create a %map consisting of copies of the elements from
00277        *  [__first,__last).  This is linear in N if the range is
00278        *  already sorted, and NlogN otherwise (where N is
00279        *  distance(__first,__last)).
00280        */
00281       template<typename _InputIterator>
00282         map(_InputIterator __first, _InputIterator __last,
00283             const _Compare& __comp,
00284             const allocator_type& __a = allocator_type())
00285         : _M_t(__comp, _Pair_alloc_type(__a))
00286         { _M_t._M_insert_unique(__first, __last); }
00287 
00288 #if __cplusplus >= 201103L
00289       /**
00290        *  The dtor only erases the elements, and note that if the elements
00291        *  themselves are pointers, the pointed-to memory is not touched in any
00292        *  way.  Managing the pointer is the user's responsibility.
00293        */
00294       ~map() = default;
00295 #endif
00296 
00297       /**
00298        *  @brief  %Map assignment operator.
00299        *
00300        *  Whether the allocator is copied depends on the allocator traits.
00301        */
00302 #if __cplusplus < 201103L
00303       map&
00304       operator=(const map& __x)
00305       {
00306         _M_t = __x._M_t;
00307         return *this;
00308       }
00309 #else
00310       map&
00311       operator=(const map&) = default;
00312 
00313       /// Move assignment operator.
00314       map&
00315       operator=(map&&) = default;
00316 
00317       /**
00318        *  @brief  %Map list assignment operator.
00319        *  @param  __l  An initializer_list.
00320        *
00321        *  This function fills a %map with copies of the elements in the
00322        *  initializer list @a __l.
00323        *
00324        *  Note that the assignment completely changes the %map and
00325        *  that the resulting %map's size is the same as the number
00326        *  of elements assigned.
00327        */
00328       map&
00329       operator=(initializer_list<value_type> __l)
00330       {
00331         _M_t._M_assign_unique(__l.begin(), __l.end());
00332         return *this;
00333       }
00334 #endif
00335 
00336       /// Get a copy of the memory allocation object.
00337       allocator_type
00338       get_allocator() const _GLIBCXX_NOEXCEPT
00339       { return allocator_type(_M_t.get_allocator()); }
00340 
00341       // iterators
00342       /**
00343        *  Returns a read/write iterator that points to the first pair in the
00344        *  %map.
00345        *  Iteration is done in ascending order according to the keys.
00346        */
00347       iterator
00348       begin() _GLIBCXX_NOEXCEPT
00349       { return _M_t.begin(); }
00350 
00351       /**
00352        *  Returns a read-only (constant) iterator that points to the first pair
00353        *  in the %map.  Iteration is done in ascending order according to the
00354        *  keys.
00355        */
00356       const_iterator
00357       begin() const _GLIBCXX_NOEXCEPT
00358       { return _M_t.begin(); }
00359 
00360       /**
00361        *  Returns a read/write iterator that points one past the last
00362        *  pair in the %map.  Iteration is done in ascending order
00363        *  according to the keys.
00364        */
00365       iterator
00366       end() _GLIBCXX_NOEXCEPT
00367       { return _M_t.end(); }
00368 
00369       /**
00370        *  Returns a read-only (constant) iterator that points one past the last
00371        *  pair in the %map.  Iteration is done in ascending order according to
00372        *  the keys.
00373        */
00374       const_iterator
00375       end() const _GLIBCXX_NOEXCEPT
00376       { return _M_t.end(); }
00377 
00378       /**
00379        *  Returns a read/write reverse iterator that points to the last pair in
00380        *  the %map.  Iteration is done in descending order according to the
00381        *  keys.
00382        */
00383       reverse_iterator
00384       rbegin() _GLIBCXX_NOEXCEPT
00385       { return _M_t.rbegin(); }
00386 
00387       /**
00388        *  Returns a read-only (constant) reverse iterator that points to the
00389        *  last pair in the %map.  Iteration is done in descending order
00390        *  according to the keys.
00391        */
00392       const_reverse_iterator
00393       rbegin() const _GLIBCXX_NOEXCEPT
00394       { return _M_t.rbegin(); }
00395 
00396       /**
00397        *  Returns a read/write reverse iterator that points to one before the
00398        *  first pair in the %map.  Iteration is done in descending order
00399        *  according to the keys.
00400        */
00401       reverse_iterator
00402       rend() _GLIBCXX_NOEXCEPT
00403       { return _M_t.rend(); }
00404 
00405       /**
00406        *  Returns a read-only (constant) reverse iterator that points to one
00407        *  before the first pair in the %map.  Iteration is done in descending
00408        *  order according to the keys.
00409        */
00410       const_reverse_iterator
00411       rend() const _GLIBCXX_NOEXCEPT
00412       { return _M_t.rend(); }
00413 
00414 #if __cplusplus >= 201103L
00415       /**
00416        *  Returns a read-only (constant) iterator that points to the first pair
00417        *  in the %map.  Iteration is done in ascending order according to the
00418        *  keys.
00419        */
00420       const_iterator
00421       cbegin() const noexcept
00422       { return _M_t.begin(); }
00423 
00424       /**
00425        *  Returns a read-only (constant) iterator that points one past the last
00426        *  pair in the %map.  Iteration is done in ascending order according to
00427        *  the keys.
00428        */
00429       const_iterator
00430       cend() const noexcept
00431       { return _M_t.end(); }
00432 
00433       /**
00434        *  Returns a read-only (constant) reverse iterator that points to the
00435        *  last pair in the %map.  Iteration is done in descending order
00436        *  according to the keys.
00437        */
00438       const_reverse_iterator
00439       crbegin() const noexcept
00440       { return _M_t.rbegin(); }
00441 
00442       /**
00443        *  Returns a read-only (constant) reverse iterator that points to one
00444        *  before the first pair in the %map.  Iteration is done in descending
00445        *  order according to the keys.
00446        */
00447       const_reverse_iterator
00448       crend() const noexcept
00449       { return _M_t.rend(); }
00450 #endif
00451 
00452       // capacity
00453       /** Returns true if the %map is empty.  (Thus begin() would equal
00454        *  end().)
00455       */
00456       bool
00457       empty() const _GLIBCXX_NOEXCEPT
00458       { return _M_t.empty(); }
00459 
00460       /** Returns the size of the %map.  */
00461       size_type
00462       size() const _GLIBCXX_NOEXCEPT
00463       { return _M_t.size(); }
00464 
00465       /** Returns the maximum size of the %map.  */
00466       size_type
00467       max_size() const _GLIBCXX_NOEXCEPT
00468       { return _M_t.max_size(); }
00469 
00470       // [23.3.1.2] element access
00471       /**
00472        *  @brief  Subscript ( @c [] ) access to %map data.
00473        *  @param  __k  The key for which data should be retrieved.
00474        *  @return  A reference to the data of the (key,data) %pair.
00475        *
00476        *  Allows for easy lookup with the subscript ( @c [] )
00477        *  operator.  Returns data associated with the key specified in
00478        *  subscript.  If the key does not exist, a pair with that key
00479        *  is created using default values, which is then returned.
00480        *
00481        *  Lookup requires logarithmic time.
00482        */
00483       mapped_type&
00484       operator[](const key_type& __k)
00485       {
00486         // concept requirements
00487         __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
00488 
00489         iterator __i = lower_bound(__k);
00490         // __i->first is greater than or equivalent to __k.
00491         if (__i == end() || key_comp()(__k, (*__i).first))
00492 #if __cplusplus >= 201103L
00493           __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
00494                                             std::tuple<const key_type&>(__k),
00495                                             std::tuple<>());
00496 #else
00497           __i = insert(__i, value_type(__k, mapped_type()));
00498 #endif
00499         return (*__i).second;
00500       }
00501 
00502 #if __cplusplus >= 201103L
00503       mapped_type&
00504       operator[](key_type&& __k)
00505       {
00506         // concept requirements
00507         __glibcxx_function_requires(_DefaultConstructibleConcept<mapped_type>)
00508 
00509         iterator __i = lower_bound(__k);
00510         // __i->first is greater than or equivalent to __k.
00511         if (__i == end() || key_comp()(__k, (*__i).first))
00512           __i = _M_t._M_emplace_hint_unique(__i, std::piecewise_construct,
00513                                         std::forward_as_tuple(std::move(__k)),
00514                                         std::tuple<>());
00515         return (*__i).second;
00516       }
00517 #endif
00518 
00519       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00520       // DR 464. Suggestion for new member functions in standard containers.
00521       /**
00522        *  @brief  Access to %map data.
00523        *  @param  __k  The key for which data should be retrieved.
00524        *  @return  A reference to the data whose key is equivalent to @a __k, if
00525        *           such a data is present in the %map.
00526        *  @throw  std::out_of_range  If no such data is present.
00527        */
00528       mapped_type&
00529       at(const key_type& __k)
00530       {
00531         iterator __i = lower_bound(__k);
00532         if (__i == end() || key_comp()(__k, (*__i).first))
00533           __throw_out_of_range(__N("map::at"));
00534         return (*__i).second;
00535       }
00536 
00537       const mapped_type&
00538       at(const key_type& __k) const
00539       {
00540         const_iterator __i = lower_bound(__k);
00541         if (__i == end() || key_comp()(__k, (*__i).first))
00542           __throw_out_of_range(__N("map::at"));
00543         return (*__i).second;
00544       }
00545 
00546       // modifiers
00547 #if __cplusplus >= 201103L
00548       /**
00549        *  @brief Attempts to build and insert a std::pair into the %map.
00550        *
00551        *  @param __args  Arguments used to generate a new pair instance (see
00552        *                std::piecewise_contruct for passing arguments to each
00553        *                part of the pair constructor).
00554        *
00555        *  @return  A pair, of which the first element is an iterator that points
00556        *           to the possibly inserted pair, and the second is a bool that
00557        *           is true if the pair was actually inserted.
00558        *
00559        *  This function attempts to build and insert a (key, value) %pair into
00560        *  the %map.
00561        *  A %map relies on unique keys and thus a %pair is only inserted if its
00562        *  first element (the key) is not already present in the %map.
00563        *
00564        *  Insertion requires logarithmic time.
00565        */
00566       template<typename... _Args>
00567         std::pair<iterator, bool>
00568         emplace(_Args&&... __args)
00569         { return _M_t._M_emplace_unique(std::forward<_Args>(__args)...); }
00570 
00571       /**
00572        *  @brief Attempts to build and insert a std::pair into the %map.
00573        *
00574        *  @param  __pos  An iterator that serves as a hint as to where the pair
00575        *                should be inserted.
00576        *  @param  __args  Arguments used to generate a new pair instance (see
00577        *                 std::piecewise_contruct for passing arguments to each
00578        *                 part of the pair constructor).
00579        *  @return An iterator that points to the element with key of the
00580        *          std::pair built from @a __args (may or may not be that
00581        *          std::pair).
00582        *
00583        *  This function is not concerned about whether the insertion took place,
00584        *  and thus does not return a boolean like the single-argument emplace()
00585        *  does.
00586        *  Note that the first parameter is only a hint and can potentially
00587        *  improve the performance of the insertion process. A bad hint would
00588        *  cause no gains in efficiency.
00589        *
00590        *  See
00591        *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
00592        *  for more on @a hinting.
00593        *
00594        *  Insertion requires logarithmic time (if the hint is not taken).
00595        */
00596       template<typename... _Args>
00597         iterator
00598         emplace_hint(const_iterator __pos, _Args&&... __args)
00599         {
00600           return _M_t._M_emplace_hint_unique(__pos,
00601                                              std::forward<_Args>(__args)...);
00602         }
00603 #endif
00604 
00605 #if __cplusplus > 201402L
00606       /// Extract a node.
00607       node_type
00608       extract(const_iterator __pos)
00609       {
00610         __glibcxx_assert(__pos != end());
00611         return _M_t.extract(__pos);
00612       }
00613 
00614       /// Extract a node.
00615       node_type
00616       extract(const key_type& __x)
00617       { return _M_t.extract(__x); }
00618 
00619       /// Re-insert an extracted node.
00620       insert_return_type
00621       insert(node_type&& __nh)
00622       { return _M_t._M_reinsert_node_unique(std::move(__nh)); }
00623 
00624       /// Re-insert an extracted node.
00625       iterator
00626       insert(const_iterator __hint, node_type&& __nh)
00627       { return _M_t._M_reinsert_node_hint_unique(__hint, std::move(__nh)); }
00628 
00629       template<typename, typename>
00630         friend class _Rb_tree_merge_helper;
00631 
00632       template<typename _C2>
00633         void
00634         merge(map<_Key, _Tp, _C2, _Alloc>& __source)
00635         {
00636           using _Merge_helper = _Rb_tree_merge_helper<map, _C2>;
00637           _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
00638         }
00639 
00640       template<typename _C2>
00641         void
00642         merge(map<_Key, _Tp, _C2, _Alloc>&& __source)
00643         { merge(__source); }
00644 
00645       template<typename _C2>
00646         void
00647         merge(multimap<_Key, _Tp, _C2, _Alloc>& __source)
00648         {
00649           using _Merge_helper = _Rb_tree_merge_helper<map, _C2>;
00650           _M_t._M_merge_unique(_Merge_helper::_S_get_tree(__source));
00651         }
00652 
00653       template<typename _C2>
00654         void
00655         merge(multimap<_Key, _Tp, _C2, _Alloc>&& __source)
00656         { merge(__source); }
00657 #endif // C++17
00658 
00659 #if __cplusplus > 201402L
00660 #define __cpp_lib_map_try_emplace 201411
00661       /**
00662        *  @brief Attempts to build and insert a std::pair into the %map.
00663        *
00664        *  @param __k    Key to use for finding a possibly existing pair in
00665        *                the map.
00666        *  @param __args  Arguments used to generate the .second for a new pair
00667        *                instance.
00668        *
00669        *  @return  A pair, of which the first element is an iterator that points
00670        *           to the possibly inserted pair, and the second is a bool that
00671        *           is true if the pair was actually inserted.
00672        *
00673        *  This function attempts to build and insert a (key, value) %pair into
00674        *  the %map.
00675        *  A %map relies on unique keys and thus a %pair is only inserted if its
00676        *  first element (the key) is not already present in the %map.
00677        *  If a %pair is not inserted, this function has no effect.
00678        *
00679        *  Insertion requires logarithmic time.
00680        */
00681       template <typename... _Args>
00682         pair<iterator, bool>
00683         try_emplace(const key_type& __k, _Args&&... __args)
00684         {
00685           iterator __i = lower_bound(__k);
00686           if (__i == end() || key_comp()(__k, (*__i).first))
00687             {
00688               __i = emplace_hint(__i, std::piecewise_construct,
00689                                  std::forward_as_tuple(__k),
00690                                  std::forward_as_tuple(
00691                                    std::forward<_Args>(__args)...));
00692               return {__i, true};
00693             }
00694           return {__i, false};
00695         }
00696 
00697       // move-capable overload
00698       template <typename... _Args>
00699         pair<iterator, bool>
00700         try_emplace(key_type&& __k, _Args&&... __args)
00701         {
00702           iterator __i = lower_bound(__k);
00703           if (__i == end() || key_comp()(__k, (*__i).first))
00704             {
00705               __i = emplace_hint(__i, std::piecewise_construct,
00706                                  std::forward_as_tuple(std::move(__k)),
00707                                  std::forward_as_tuple(
00708                                    std::forward<_Args>(__args)...));
00709               return {__i, true};
00710             }
00711           return {__i, false};
00712         }
00713 
00714       /**
00715        *  @brief Attempts to build and insert a std::pair into the %map.
00716        *
00717        *  @param  __hint  An iterator that serves as a hint as to where the
00718        *                  pair should be inserted.
00719        *  @param __k    Key to use for finding a possibly existing pair in
00720        *                the map.
00721        *  @param __args  Arguments used to generate the .second for a new pair
00722        *                instance.
00723        *  @return An iterator that points to the element with key of the
00724        *          std::pair built from @a __args (may or may not be that
00725        *          std::pair).
00726        *
00727        *  This function is not concerned about whether the insertion took place,
00728        *  and thus does not return a boolean like the single-argument
00729        *  try_emplace() does. However, if insertion did not take place,
00730        *  this function has no effect.
00731        *  Note that the first parameter is only a hint and can potentially
00732        *  improve the performance of the insertion process. A bad hint would
00733        *  cause no gains in efficiency.
00734        *
00735        *  See
00736        *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
00737        *  for more on @a hinting.
00738        *
00739        *  Insertion requires logarithmic time (if the hint is not taken).
00740        */
00741       template <typename... _Args>
00742         iterator
00743         try_emplace(const_iterator __hint, const key_type& __k,
00744                     _Args&&... __args)
00745         {
00746           iterator __i;
00747           auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
00748           if (__true_hint.second)
00749             __i = emplace_hint(iterator(__true_hint.second),
00750                                std::piecewise_construct,
00751                                std::forward_as_tuple(__k),
00752                                std::forward_as_tuple(
00753                                  std::forward<_Args>(__args)...));
00754           else
00755             __i = iterator(__true_hint.first);
00756           return __i;
00757         }
00758 
00759       // move-capable overload
00760       template <typename... _Args>
00761         iterator
00762         try_emplace(const_iterator __hint, key_type&& __k, _Args&&... __args)
00763         {
00764           iterator __i;
00765           auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
00766           if (__true_hint.second)
00767             __i = emplace_hint(iterator(__true_hint.second),
00768                                std::piecewise_construct,
00769                                std::forward_as_tuple(std::move(__k)),
00770                                std::forward_as_tuple(
00771                                  std::forward<_Args>(__args)...));
00772           else
00773             __i = iterator(__true_hint.first);
00774           return __i;
00775         }
00776 #endif
00777 
00778       /**
00779        *  @brief Attempts to insert a std::pair into the %map.
00780        *  @param __x Pair to be inserted (see std::make_pair for easy
00781        *             creation of pairs).
00782        *
00783        *  @return  A pair, of which the first element is an iterator that
00784        *           points to the possibly inserted pair, and the second is
00785        *           a bool that is true if the pair was actually inserted.
00786        *
00787        *  This function attempts to insert a (key, value) %pair into the %map.
00788        *  A %map relies on unique keys and thus a %pair is only inserted if its
00789        *  first element (the key) is not already present in the %map.
00790        *
00791        *  Insertion requires logarithmic time.
00792        *  @{
00793        */
00794       std::pair<iterator, bool>
00795       insert(const value_type& __x)
00796       { return _M_t._M_insert_unique(__x); }
00797 
00798 #if __cplusplus >= 201103L
00799       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00800       // 2354. Unnecessary copying when inserting into maps with braced-init
00801       std::pair<iterator, bool>
00802       insert(value_type&& __x)
00803       { return _M_t._M_insert_unique(std::move(__x)); }
00804 
00805       template<typename _Pair, typename = typename
00806                std::enable_if<std::is_constructible<value_type,
00807                                                     _Pair&&>::value>::type>
00808         std::pair<iterator, bool>
00809         insert(_Pair&& __x)
00810         { return _M_t._M_insert_unique(std::forward<_Pair>(__x)); }
00811 #endif
00812       // @}
00813 
00814 #if __cplusplus >= 201103L
00815       /**
00816        *  @brief Attempts to insert a list of std::pairs into the %map.
00817        *  @param  __list  A std::initializer_list<value_type> of pairs to be
00818        *                  inserted.
00819        *
00820        *  Complexity similar to that of the range constructor.
00821        */
00822       void
00823       insert(std::initializer_list<value_type> __list)
00824       { insert(__list.begin(), __list.end()); }
00825 #endif
00826 
00827       /**
00828        *  @brief Attempts to insert a std::pair into the %map.
00829        *  @param  __position  An iterator that serves as a hint as to where the
00830        *                    pair should be inserted.
00831        *  @param  __x  Pair to be inserted (see std::make_pair for easy creation
00832        *               of pairs).
00833        *  @return An iterator that points to the element with key of
00834        *           @a __x (may or may not be the %pair passed in).
00835        *
00836 
00837        *  This function is not concerned about whether the insertion
00838        *  took place, and thus does not return a boolean like the
00839        *  single-argument insert() does.  Note that the first
00840        *  parameter is only a hint and can potentially improve the
00841        *  performance of the insertion process.  A bad hint would
00842        *  cause no gains in efficiency.
00843        *
00844        *  See
00845        *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/associative.html#containers.associative.insert_hints
00846        *  for more on @a hinting.
00847        *
00848        *  Insertion requires logarithmic time (if the hint is not taken).
00849        *  @{
00850        */
00851       iterator
00852 #if __cplusplus >= 201103L
00853       insert(const_iterator __position, const value_type& __x)
00854 #else
00855       insert(iterator __position, const value_type& __x)
00856 #endif
00857       { return _M_t._M_insert_unique_(__position, __x); }
00858 
00859 #if __cplusplus >= 201103L
00860       // _GLIBCXX_RESOLVE_LIB_DEFECTS
00861       // 2354. Unnecessary copying when inserting into maps with braced-init
00862       iterator
00863       insert(const_iterator __position, value_type&& __x)
00864       { return _M_t._M_insert_unique_(__position, std::move(__x)); }
00865 
00866       template<typename _Pair, typename = typename
00867                std::enable_if<std::is_constructible<value_type,
00868                                                     _Pair&&>::value>::type>
00869         iterator
00870         insert(const_iterator __position, _Pair&& __x)
00871         { return _M_t._M_insert_unique_(__position,
00872                                         std::forward<_Pair>(__x)); }
00873 #endif
00874       // @}
00875 
00876       /**
00877        *  @brief Template function that attempts to insert a range of elements.
00878        *  @param  __first  Iterator pointing to the start of the range to be
00879        *                   inserted.
00880        *  @param  __last  Iterator pointing to the end of the range.
00881        *
00882        *  Complexity similar to that of the range constructor.
00883        */
00884       template<typename _InputIterator>
00885         void
00886         insert(_InputIterator __first, _InputIterator __last)
00887         { _M_t._M_insert_unique(__first, __last); }
00888 
00889 #if __cplusplus > 201402L
00890 #define __cpp_lib_map_insertion 201411
00891       /**
00892        *  @brief Attempts to insert or assign a std::pair into the %map.
00893        *  @param __k    Key to use for finding a possibly existing pair in
00894        *                the map.
00895        *  @param __obj  Argument used to generate the .second for a pair
00896        *                instance.
00897        *
00898        *  @return  A pair, of which the first element is an iterator that
00899        *           points to the possibly inserted pair, and the second is
00900        *           a bool that is true if the pair was actually inserted.
00901        *
00902        *  This function attempts to insert a (key, value) %pair into the %map.
00903        *  A %map relies on unique keys and thus a %pair is only inserted if its
00904        *  first element (the key) is not already present in the %map.
00905        *  If the %pair was already in the %map, the .second of the %pair
00906        *  is assigned from __obj.
00907        *
00908        *  Insertion requires logarithmic time.
00909        */
00910       template <typename _Obj>
00911         pair<iterator, bool>
00912         insert_or_assign(const key_type& __k, _Obj&& __obj)
00913         {
00914           iterator __i = lower_bound(__k);
00915           if (__i == end() || key_comp()(__k, (*__i).first))
00916             {
00917               __i = emplace_hint(__i, std::piecewise_construct,
00918                                  std::forward_as_tuple(__k),
00919                                  std::forward_as_tuple(
00920                                    std::forward<_Obj>(__obj)));
00921               return {__i, true};
00922             }
00923           (*__i).second = std::forward<_Obj>(__obj);
00924           return {__i, false};
00925         }
00926 
00927       // move-capable overload
00928       template <typename _Obj>
00929         pair<iterator, bool>
00930         insert_or_assign(key_type&& __k, _Obj&& __obj)
00931         {
00932           iterator __i = lower_bound(__k);
00933           if (__i == end() || key_comp()(__k, (*__i).first))
00934             {
00935               __i = emplace_hint(__i, std::piecewise_construct,
00936                                  std::forward_as_tuple(std::move(__k)),
00937                                  std::forward_as_tuple(
00938                                    std::forward<_Obj>(__obj)));
00939               return {__i, true};
00940             }
00941           (*__i).second = std::forward<_Obj>(__obj);
00942           return {__i, false};
00943         }
00944 
00945       /**
00946        *  @brief Attempts to insert or assign a std::pair into the %map.
00947        *  @param  __hint  An iterator that serves as a hint as to where the
00948        *                  pair should be inserted.
00949        *  @param __k    Key to use for finding a possibly existing pair in
00950        *                the map.
00951        *  @param __obj  Argument used to generate the .second for a pair
00952        *                instance.
00953        *
00954        *  @return An iterator that points to the element with key of
00955        *           @a __x (may or may not be the %pair passed in).
00956        *
00957        *  This function attempts to insert a (key, value) %pair into the %map.
00958        *  A %map relies on unique keys and thus a %pair is only inserted if its
00959        *  first element (the key) is not already present in the %map.
00960        *  If the %pair was already in the %map, the .second of the %pair
00961        *  is assigned from __obj.
00962        *
00963        *  Insertion requires logarithmic time.
00964        */
00965       template <typename _Obj>
00966         iterator
00967         insert_or_assign(const_iterator __hint,
00968                          const key_type& __k, _Obj&& __obj)
00969         {
00970           iterator __i;
00971           auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
00972           if (__true_hint.second)
00973             {
00974               return emplace_hint(iterator(__true_hint.second),
00975                                   std::piecewise_construct,
00976                                   std::forward_as_tuple(__k),
00977                                   std::forward_as_tuple(
00978                                     std::forward<_Obj>(__obj)));
00979             }
00980           __i = iterator(__true_hint.first);
00981           (*__i).second = std::forward<_Obj>(__obj);
00982           return __i;
00983         }
00984 
00985       // move-capable overload
00986       template <typename _Obj>
00987         iterator
00988         insert_or_assign(const_iterator __hint, key_type&& __k, _Obj&& __obj)
00989         {
00990           iterator __i;
00991           auto __true_hint = _M_t._M_get_insert_hint_unique_pos(__hint, __k);
00992           if (__true_hint.second)
00993             {
00994               return emplace_hint(iterator(__true_hint.second),
00995                                   std::piecewise_construct,
00996                                   std::forward_as_tuple(std::move(__k)),
00997                                   std::forward_as_tuple(
00998                                     std::forward<_Obj>(__obj)));
00999             }
01000           __i = iterator(__true_hint.first);
01001           (*__i).second = std::forward<_Obj>(__obj);
01002           return __i;
01003         }
01004 #endif
01005 
01006 #if __cplusplus >= 201103L
01007       // _GLIBCXX_RESOLVE_LIB_DEFECTS
01008       // DR 130. Associative erase should return an iterator.
01009       /**
01010        *  @brief Erases an element from a %map.
01011        *  @param  __position  An iterator pointing to the element to be erased.
01012        *  @return An iterator pointing to the element immediately following
01013        *          @a position prior to the element being erased. If no such
01014        *          element exists, end() is returned.
01015        *
01016        *  This function erases an element, pointed to by the given
01017        *  iterator, from a %map.  Note that this function only erases
01018        *  the element, and that if the element is itself a pointer,
01019        *  the pointed-to memory is not touched in any way.  Managing
01020        *  the pointer is the user's responsibility.
01021        *
01022        *  @{
01023        */
01024       iterator
01025       erase(const_iterator __position)
01026       { return _M_t.erase(__position); }
01027 
01028       // LWG 2059
01029       _GLIBCXX_ABI_TAG_CXX11
01030       iterator
01031       erase(iterator __position)
01032       { return _M_t.erase(__position); }
01033       // @}
01034 #else
01035       /**
01036        *  @brief Erases an element from a %map.
01037        *  @param  __position  An iterator pointing to the element to be erased.
01038        *
01039        *  This function erases an element, pointed to by the given
01040        *  iterator, from a %map.  Note that this function only erases
01041        *  the element, and that if the element is itself a pointer,
01042        *  the pointed-to memory is not touched in any way.  Managing
01043        *  the pointer is the user's responsibility.
01044        */
01045       void
01046       erase(iterator __position)
01047       { _M_t.erase(__position); }
01048 #endif
01049 
01050       /**
01051        *  @brief Erases elements according to the provided key.
01052        *  @param  __x  Key of element to be erased.
01053        *  @return  The number of elements erased.
01054        *
01055        *  This function erases all the elements located by the given key from
01056        *  a %map.
01057        *  Note that this function only erases the element, and that if
01058        *  the element is itself a pointer, the pointed-to memory is not touched
01059        *  in any way.  Managing the pointer is the user's responsibility.
01060        */
01061       size_type
01062       erase(const key_type& __x)
01063       { return _M_t.erase(__x); }
01064 
01065 #if __cplusplus >= 201103L
01066       // _GLIBCXX_RESOLVE_LIB_DEFECTS
01067       // DR 130. Associative erase should return an iterator.
01068       /**
01069        *  @brief Erases a [first,last) range of elements from a %map.
01070        *  @param  __first  Iterator pointing to the start of the range to be
01071        *                   erased.
01072        *  @param __last Iterator pointing to the end of the range to
01073        *                be erased.
01074        *  @return The iterator @a __last.
01075        *
01076        *  This function erases a sequence of elements from a %map.
01077        *  Note that this function only erases the element, and that if
01078        *  the element is itself a pointer, the pointed-to memory is not touched
01079        *  in any way.  Managing the pointer is the user's responsibility.
01080        */
01081       iterator
01082       erase(const_iterator __first, const_iterator __last)
01083       { return _M_t.erase(__first, __last); }
01084 #else
01085       /**
01086        *  @brief Erases a [__first,__last) range of elements from a %map.
01087        *  @param  __first  Iterator pointing to the start of the range to be
01088        *                   erased.
01089        *  @param __last Iterator pointing to the end of the range to
01090        *                be erased.
01091        *
01092        *  This function erases a sequence of elements from a %map.
01093        *  Note that this function only erases the element, and that if
01094        *  the element is itself a pointer, the pointed-to memory is not touched
01095        *  in any way.  Managing the pointer is the user's responsibility.
01096        */
01097       void
01098       erase(iterator __first, iterator __last)
01099       { _M_t.erase(__first, __last); }
01100 #endif
01101 
01102       /**
01103        *  @brief  Swaps data with another %map.
01104        *  @param  __x  A %map of the same element and allocator types.
01105        *
01106        *  This exchanges the elements between two maps in constant
01107        *  time.  (It is only swapping a pointer, an integer, and an
01108        *  instance of the @c Compare type (which itself is often
01109        *  stateless and empty), so it should be quite fast.)  Note
01110        *  that the global std::swap() function is specialized such
01111        *  that std::swap(m1,m2) will feed to this function.
01112        *
01113        *  Whether the allocators are swapped depends on the allocator traits.
01114        */
01115       void
01116       swap(map& __x)
01117       _GLIBCXX_NOEXCEPT_IF(__is_nothrow_swappable<_Compare>::value)
01118       { _M_t.swap(__x._M_t); }
01119 
01120       /**
01121        *  Erases all elements in a %map.  Note that this function only
01122        *  erases the elements, and that if the elements themselves are
01123        *  pointers, the pointed-to memory is not touched in any way.
01124        *  Managing the pointer is the user's responsibility.
01125        */
01126       void
01127       clear() _GLIBCXX_NOEXCEPT
01128       { _M_t.clear(); }
01129 
01130       // observers
01131       /**
01132        *  Returns the key comparison object out of which the %map was
01133        *  constructed.
01134        */
01135       key_compare
01136       key_comp() const
01137       { return _M_t.key_comp(); }
01138 
01139       /**
01140        *  Returns a value comparison object, built from the key comparison
01141        *  object out of which the %map was constructed.
01142        */
01143       value_compare
01144       value_comp() const
01145       { return value_compare(_M_t.key_comp()); }
01146 
01147       // [23.3.1.3] map operations
01148 
01149       //@{
01150       /**
01151        *  @brief Tries to locate an element in a %map.
01152        *  @param  __x  Key of (key, value) %pair to be located.
01153        *  @return  Iterator pointing to sought-after element, or end() if not
01154        *           found.
01155        *
01156        *  This function takes a key and tries to locate the element with which
01157        *  the key matches.  If successful the function returns an iterator
01158        *  pointing to the sought after %pair.  If unsuccessful it returns the
01159        *  past-the-end ( @c end() ) iterator.
01160        */
01161 
01162       iterator
01163       find(const key_type& __x)
01164       { return _M_t.find(__x); }
01165 
01166 #if __cplusplus > 201103L
01167       template<typename _Kt>
01168         auto
01169         find(const _Kt& __x) -> decltype(_M_t._M_find_tr(__x))
01170         { return _M_t._M_find_tr(__x); }
01171 #endif
01172       //@}
01173 
01174       //@{
01175       /**
01176        *  @brief Tries to locate an element in a %map.
01177        *  @param  __x  Key of (key, value) %pair to be located.
01178        *  @return  Read-only (constant) iterator pointing to sought-after
01179        *           element, or end() if not found.
01180        *
01181        *  This function takes a key and tries to locate the element with which
01182        *  the key matches.  If successful the function returns a constant
01183        *  iterator pointing to the sought after %pair. If unsuccessful it
01184        *  returns the past-the-end ( @c end() ) iterator.
01185        */
01186 
01187       const_iterator
01188       find(const key_type& __x) const
01189       { return _M_t.find(__x); }
01190 
01191 #if __cplusplus > 201103L
01192       template<typename _Kt>
01193         auto
01194         find(const _Kt& __x) const -> decltype(_M_t._M_find_tr(__x))
01195         { return _M_t._M_find_tr(__x); }
01196 #endif
01197       //@}
01198 
01199       //@{
01200       /**
01201        *  @brief  Finds the number of elements with given key.
01202        *  @param  __x  Key of (key, value) pairs to be located.
01203        *  @return  Number of elements with specified key.
01204        *
01205        *  This function only makes sense for multimaps; for map the result will
01206        *  either be 0 (not present) or 1 (present).
01207        */
01208       size_type
01209       count(const key_type& __x) const
01210       { return _M_t.find(__x) == _M_t.end() ? 0 : 1; }
01211 
01212 #if __cplusplus > 201103L
01213       template<typename _Kt>
01214         auto
01215         count(const _Kt& __x) const -> decltype(_M_t._M_count_tr(__x))
01216         { return _M_t._M_count_tr(__x); }
01217 #endif
01218       //@}
01219 
01220       //@{
01221       /**
01222        *  @brief Finds the beginning of a subsequence matching given key.
01223        *  @param  __x  Key of (key, value) pair to be located.
01224        *  @return  Iterator pointing to first element equal to or greater
01225        *           than key, or end().
01226        *
01227        *  This function returns the first element of a subsequence of elements
01228        *  that matches the given key.  If unsuccessful it returns an iterator
01229        *  pointing to the first element that has a greater value than given key
01230        *  or end() if no such element exists.
01231        */
01232       iterator
01233       lower_bound(const key_type& __x)
01234       { return _M_t.lower_bound(__x); }
01235 
01236 #if __cplusplus > 201103L
01237       template<typename _Kt>
01238         auto
01239         lower_bound(const _Kt& __x)
01240         -> decltype(iterator(_M_t._M_lower_bound_tr(__x)))
01241         { return iterator(_M_t._M_lower_bound_tr(__x)); }
01242 #endif
01243       //@}
01244 
01245       //@{
01246       /**
01247        *  @brief Finds the beginning of a subsequence matching given key.
01248        *  @param  __x  Key of (key, value) pair to be located.
01249        *  @return  Read-only (constant) iterator pointing to first element
01250        *           equal to or greater than key, or end().
01251        *
01252        *  This function returns the first element of a subsequence of elements
01253        *  that matches the given key.  If unsuccessful it returns an iterator
01254        *  pointing to the first element that has a greater value than given key
01255        *  or end() if no such element exists.
01256        */
01257       const_iterator
01258       lower_bound(const key_type& __x) const
01259       { return _M_t.lower_bound(__x); }
01260 
01261 #if __cplusplus > 201103L
01262       template<typename _Kt>
01263         auto
01264         lower_bound(const _Kt& __x) const
01265         -> decltype(const_iterator(_M_t._M_lower_bound_tr(__x)))
01266         { return const_iterator(_M_t._M_lower_bound_tr(__x)); }
01267 #endif
01268       //@}
01269 
01270       //@{
01271       /**
01272        *  @brief Finds the end of a subsequence matching given key.
01273        *  @param  __x  Key of (key, value) pair to be located.
01274        *  @return Iterator pointing to the first element
01275        *          greater than key, or end().
01276        */
01277       iterator
01278       upper_bound(const key_type& __x)
01279       { return _M_t.upper_bound(__x); }
01280 
01281 #if __cplusplus > 201103L
01282       template<typename _Kt>
01283         auto
01284         upper_bound(const _Kt& __x)
01285         -> decltype(iterator(_M_t._M_upper_bound_tr(__x)))
01286         { return iterator(_M_t._M_upper_bound_tr(__x)); }
01287 #endif
01288       //@}
01289 
01290       //@{
01291       /**
01292        *  @brief Finds the end of a subsequence matching given key.
01293        *  @param  __x  Key of (key, value) pair to be located.
01294        *  @return  Read-only (constant) iterator pointing to first iterator
01295        *           greater than key, or end().
01296        */
01297       const_iterator
01298       upper_bound(const key_type& __x) const
01299       { return _M_t.upper_bound(__x); }
01300 
01301 #if __cplusplus > 201103L
01302       template<typename _Kt>
01303         auto
01304         upper_bound(const _Kt& __x) const
01305         -> decltype(const_iterator(_M_t._M_upper_bound_tr(__x)))
01306         { return const_iterator(_M_t._M_upper_bound_tr(__x)); }
01307 #endif
01308       //@}
01309 
01310       //@{
01311       /**
01312        *  @brief Finds a subsequence matching given key.
01313        *  @param  __x  Key of (key, value) pairs to be located.
01314        *  @return  Pair of iterators that possibly points to the subsequence
01315        *           matching given key.
01316        *
01317        *  This function is equivalent to
01318        *  @code
01319        *    std::make_pair(c.lower_bound(val),
01320        *                   c.upper_bound(val))
01321        *  @endcode
01322        *  (but is faster than making the calls separately).
01323        *
01324        *  This function probably only makes sense for multimaps.
01325        */
01326       std::pair<iterator, iterator>
01327       equal_range(const key_type& __x)
01328       { return _M_t.equal_range(__x); }
01329 
01330 #if __cplusplus > 201103L
01331       template<typename _Kt>
01332         auto
01333         equal_range(const _Kt& __x)
01334         -> decltype(pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)))
01335         { return pair<iterator, iterator>(_M_t._M_equal_range_tr(__x)); }
01336 #endif
01337       //@}
01338 
01339       //@{
01340       /**
01341        *  @brief Finds a subsequence matching given key.
01342        *  @param  __x  Key of (key, value) pairs to be located.
01343        *  @return  Pair of read-only (constant) iterators that possibly points
01344        *           to the subsequence matching given key.
01345        *
01346        *  This function is equivalent to
01347        *  @code
01348        *    std::make_pair(c.lower_bound(val),
01349        *                   c.upper_bound(val))
01350        *  @endcode
01351        *  (but is faster than making the calls separately).
01352        *
01353        *  This function probably only makes sense for multimaps.
01354        */
01355       std::pair<const_iterator, const_iterator>
01356       equal_range(const key_type& __x) const
01357       { return _M_t.equal_range(__x); }
01358 
01359 #if __cplusplus > 201103L
01360       template<typename _Kt>
01361         auto
01362         equal_range(const _Kt& __x) const
01363         -> decltype(pair<const_iterator, const_iterator>(
01364               _M_t._M_equal_range_tr(__x)))
01365         {
01366           return pair<const_iterator, const_iterator>(
01367               _M_t._M_equal_range_tr(__x));
01368         }
01369 #endif
01370       //@}
01371 
01372       template<typename _K1, typename _T1, typename _C1, typename _A1>
01373         friend bool
01374         operator==(const map<_K1, _T1, _C1, _A1>&,
01375                    const map<_K1, _T1, _C1, _A1>&);
01376 
01377       template<typename _K1, typename _T1, typename _C1, typename _A1>
01378         friend bool
01379         operator<(const map<_K1, _T1, _C1, _A1>&,
01380                   const map<_K1, _T1, _C1, _A1>&);
01381     };
01382 
01383   /**
01384    *  @brief  Map equality comparison.
01385    *  @param  __x  A %map.
01386    *  @param  __y  A %map of the same type as @a x.
01387    *  @return  True iff the size and elements of the maps are equal.
01388    *
01389    *  This is an equivalence relation.  It is linear in the size of the
01390    *  maps.  Maps are considered equivalent if their sizes are equal,
01391    *  and if corresponding elements compare equal.
01392   */
01393   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
01394     inline bool
01395     operator==(const map<_Key, _Tp, _Compare, _Alloc>& __x,
01396                const map<_Key, _Tp, _Compare, _Alloc>& __y)
01397     { return __x._M_t == __y._M_t; }
01398 
01399   /**
01400    *  @brief  Map ordering relation.
01401    *  @param  __x  A %map.
01402    *  @param  __y  A %map of the same type as @a x.
01403    *  @return  True iff @a x is lexicographically less than @a y.
01404    *
01405    *  This is a total ordering relation.  It is linear in the size of the
01406    *  maps.  The elements must be comparable with @c <.
01407    *
01408    *  See std::lexicographical_compare() for how the determination is made.
01409   */
01410   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
01411     inline bool
01412     operator<(const map<_Key, _Tp, _Compare, _Alloc>& __x,
01413               const map<_Key, _Tp, _Compare, _Alloc>& __y)
01414     { return __x._M_t < __y._M_t; }
01415 
01416   /// Based on operator==
01417   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
01418     inline bool
01419     operator!=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
01420                const map<_Key, _Tp, _Compare, _Alloc>& __y)
01421     { return !(__x == __y); }
01422 
01423   /// Based on operator<
01424   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
01425     inline bool
01426     operator>(const map<_Key, _Tp, _Compare, _Alloc>& __x,
01427               const map<_Key, _Tp, _Compare, _Alloc>& __y)
01428     { return __y < __x; }
01429 
01430   /// Based on operator<
01431   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
01432     inline bool
01433     operator<=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
01434                const map<_Key, _Tp, _Compare, _Alloc>& __y)
01435     { return !(__y < __x); }
01436 
01437   /// Based on operator<
01438   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
01439     inline bool
01440     operator>=(const map<_Key, _Tp, _Compare, _Alloc>& __x,
01441                const map<_Key, _Tp, _Compare, _Alloc>& __y)
01442     { return !(__x < __y); }
01443 
01444   /// See std::map::swap().
01445   template<typename _Key, typename _Tp, typename _Compare, typename _Alloc>
01446     inline void
01447     swap(map<_Key, _Tp, _Compare, _Alloc>& __x,
01448          map<_Key, _Tp, _Compare, _Alloc>& __y)
01449     _GLIBCXX_NOEXCEPT_IF(noexcept(__x.swap(__y)))
01450     { __x.swap(__y); }
01451 
01452 _GLIBCXX_END_NAMESPACE_CONTAINER
01453 
01454 #if __cplusplus > 201402L
01455 _GLIBCXX_BEGIN_NAMESPACE_VERSION
01456   // Allow std::map access to internals of compatible maps.
01457   template<typename _Key, typename _Val, typename _Cmp1, typename _Alloc,
01458            typename _Cmp2>
01459     struct
01460     _Rb_tree_merge_helper<_GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>,
01461                           _Cmp2>
01462     {
01463     private:
01464       friend class _GLIBCXX_STD_C::map<_Key, _Val, _Cmp1, _Alloc>;
01465 
01466       static auto&
01467       _S_get_tree(_GLIBCXX_STD_C::map<_Key, _Val, _Cmp2, _Alloc>& __map)
01468       { return __map._M_t; }
01469 
01470       static auto&
01471       _S_get_tree(_GLIBCXX_STD_C::multimap<_Key, _Val, _Cmp2, _Alloc>& __map)
01472       { return __map._M_t; }
01473     };
01474 _GLIBCXX_END_NAMESPACE_VERSION
01475 #endif // C++17
01476 
01477 } // namespace std
01478 
01479 #endif /* _STL_MAP_H */